What is it like to be a bat? Thomas Nagel (1974) Arthur Franz Frankfurt Institute for Advanced Studies http://fias.uni-frankfurt.de FIAS, 2008-4-4

Main topic: the mind-body problem Can be hope that reductionism can ever be successful in this case? Terminology, Synonyms: reductionism / physicalism / materialism Consciousness / subjective experience / phenomenological features

Reductionism and its analogies Examples: Sound is a wave Heat is the motion of particles Mental states are states of the body? (physicalism) Mental events are physical events? (physicalism) Nagel: the problem of consciousness is unique. Why?

„something it is like to be“ What does it mean that an organism has conscious experience? Nagel: there is something it is like to be that organism. An organism has conscious mental states if and only if there is something like to be that organism for that orgasm. = subjective character of experience

Implication for a reduction All previous attempts of reduction do not capture subjective experience for they are all logically compatible with its absence. If physicalism wants to survive it has to capture subjective experience.

What is it like to be a bat? Assumption: we all believe that bats have experience. There is something it is like to be a bat. But can we know what it is like to be a bat for a bat? We could imagine what it would be like for us to be a bat. But for a bat? Imagination fails. Gradual transformation fails. Any extrapolation from our own case must fail. The subjective experience of a bat is inaccessible to us!

Inaccessible => non-existent? If true, a Martian would also be led to the conclusion that our subjective experience doesn't exist. Which is obviously false. We are able to recognize the existence of facts that are inaccessible to humans. What have we gained?

Points of view Facts about subjective experience embody a particular point of view. Point of view not only accessible to a single individual. One can adopt a point of view from someone sufficiently similar to oneself.

Where reduction fails (1) Nagel‘s argument: If the facts of experience are accessible only from the point of view of an organism then they can not be explained by the physical operation of that organism. Because physics is a domain of objective facts par excellence.

About objectivity The objective nature of things is observable from a specific point of view but external to it. Examples: understanding lightning, sound, rainbow,... Objectivity: a direction in which understanding can travel. A travel away from a individual/species-specific point of view.

Reduction and objectivity Reduction is characterized by reducing our dependance on our species-specific point of view. The less dependent we are on our point of view, the more objective is our description. During reduction we leave our species-specific point of view. Examples: sound, heat

Where reduction fails (2) The point of view is the essence of subjective experience. And not only a point of view on it. Any reduction would force us to abandon the point of view towards greater objectivity and therefore also the essence of the phenomenon. subjective experience   -------------------> objectivity point of view  ------------------->                                              reduction

Conclusions Mistake to conclude that physicalism is false. Rather: physicalism is a position we cannot understand. Nagel's speculative proposal: building an objective phenomenology?

Thank you!